One of the things I really think makes the Spierigs the right guys to make this - their film Daybreakers has the same kind of lonesomeness that makes so much of The Dark Crystal unsettling. It's all about atmosphere. The reason it scared me so much as a kid, and still gives me the heebie-jeebies today is because it feels very much like a world with little life left. There are only a certain number of Mystics and Skeksis, only two Gelflings, and just a handful of various other creatures. It's a scary world, and it's exactly what they're fighting for - to restore life and hope with a new population.